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Molality question

  1. Feb 6, 2005 #1
    How do I find the molality of an aqueous solution containing 1g/L of a certain protein with molar mass 9.0 x 10^4 g/mol if the density of the solution is 1g/(cm^3)??
  2. jcsd
  3. Feb 6, 2005 #2


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    Molality is expressed with mole of the solute in one kilogram of solution. Try this approach first.
  4. Feb 6, 2005 #3
    My book says molality is moles of solute over kilograms solvent.

    My question/problem is how to find the kilograms of solvent :surprised
  5. Feb 6, 2005 #4


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    U needn't.Use what Chem_Tr told u and a bit of logics.Just to get u started

    1g protein--------------------->1L solution
    1g solution--------------------->1 cc solution

    1g protein--------------------->x Kg solution...

    Why didn't i pick "g solution" in the last line??Because u need to find moles protein/Kg solution...

  6. Feb 7, 2005 #5


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    You may assume that adding a gram of protein to a liter of water does not change its volume (or the density).
  7. Feb 7, 2005 #6
    In that case...yes!--I can find it
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